Egg carton or the like



A ril 20, 1965 R. M. HOLMES EGG CARTON OR THE LIKE Filed July 17, 1962 FIG. 1

INVENT OR. RAYNOR M. HOLMES United States Patent 3,179,324 EGG CARTON OR'THE'LIKE Raynor M. Holmes, Newark, N.Y., assignor to Riegel Paper Corporation, New York, N.Y., a corporation of Delaware Filed July 17, 1962, Ser. No. 210,453 11 Claims. (Cl. 229-28) board, is cut, scored and folded to provide a body structure consisting of bottom, front and back walls, a central partition, and a cover, and the body thus formed is divided transversely by a plurality of divider elements to form a plurality of cell-like compartments, typically for holding one dozen eggs. The bottom structure of the patented cartons is formed of two bottom wall panels, arranged in an inverted V-shaped configuration, and supporting elements, integral with a central longitudinal partition of the carton body, project downward through the center of the bottom wall structure to support the center of the inverted V-shaped bottom. Cartons thus constructed provide particularly efficient cushioning protection for articles contained in the compartment cells which, of course, is of special importance in the packaging of eggs. It has been found, however, that the above-described cartons formed of paperboard, when exposed for long periods of time to atmosphere of high humidity, may become weakened through absorption of moisture by the paperboard and subsequent softening of the carton walls. If sufficient moisture is absorbed by the paperboard material, the bottom wall of the carton may soften and sag, to such an extent in extreme cases that the bottom wall will engage a base supporting surface and no longer provide a yielding or cushioned support for the contained articles.

As a principal objective of the present invention, specific improvements are made in foldable egg cartons, particularly of the type described in the beforementioned Inman patents, to the end that the bottom wall structure of the carton is strengthened and reinforced in significant respects, to offer increased resistance to sagging or other deformation upon any occasion that the paperboard material becomes softened through moisture absorption. The improved and strengthened carton bottom structure is realized, moreover, without altering or compromising other advantageous features of the carton construction and without requiring significant, if any, redesign of the carton erecting machinery.

More specifically, the invention provides a novel and improved foldable cellular carton of the type having an inverted V-shaped bottom and a plurality of transverse divider elements, in which selected ones of the divider elements are provided with downwardly projecting locking tabs of inverted T-shaped configuration arranged to extend through the apex area of the bottom wall and to engage lockingly with the lower surface of the bottom wall to assure retention of the desired, inverted V-shaped bottom wall configuration, notwithstanding substantial softening of the paperboard material of which the bottom wall is formed. Advantageously, the downwardly extending locking tabs have lower edge extremities lying in the base plane defined by the outer longitudinal edges of the bottom wall panels such that, when the carton is resting upon a supporting surface, tthe locking tabs are supported directly by the surface to prevent excessive sagging of the bottom wall panels, even though substantially softened, without, however, effecting any significant reduction in the cushioned support for the eggs or other articles contained in the carton.

In accordance with one of the more specific aspects of the invention, the carton construction includes a central, longitudinal partition, formed of a pair of partition panels connected along their top edges and folded back to back. The inverted V-shaped bottom wall is comprised of a pair of bottom wall panels foldably connected along their inner edges tothe bottom edges of the central partition, and the center of the bottom wall is supported by tablike supporting elements cut from the bottom wall panel and remaining integral with the central partition panels. These supporting elements, in the erected carton, project downward through the bottom wall and have their lower edge extremities lying in the base plane defined by the outer longitudinal edges of the bottom wall panels. Desirable and advantageous accommodation of locking tabs of inverted T-shaped configuration is provided in part by the cut-out openings from which the supporting elements are taken and in part by cut-out enlargements of such openings providing, in the erected carton, openings of keyhole configuration having adjacent enlarged and reduced areas. Thus, when the carton is erected, the tab carrying dividers may be folded from horizontal to vertical disposition, with the enlarged head portion of the T-shaped locking tab being received in the enlarged area of the keyhole shaped opening during the erecting operation, and the stern portion of the T-shaped locking tab being received in the narrower or reduced portion of the keyhole shaped opening in the fully erected carton. The described arrangement is particularly advantageous in that it permits the desired bottom wall reinforcement to be achieved without significant variation in the basic carton structure of, for example, the cartons of the beforementioned Inman patents.

For a better understanding of the above and other new and advantageous features of the invention, reference should bemade to the following detailed description and to the accompanying drawing, in which:

FIG. 1 is a plan view of a blank of paperboard or like sheet material used in the formation of the carton of the invention;

FIG. 2 is a fragmentary top plan view of the erected carton of the invention, with the cover structure broken away; and

FIG. 3 is an end elevation of the erected carton of the invention.

Referring now to the drawing, and initially to FIG. 1 thereof, the reference numberal 10 designates generally a blank of substantially rectangular form, formed of paperboard or like material. The blank is provided with a plurality of score lines 11-19 which extend across the short dimension of the blank but are referred to herein as longitudinal scores, since they extend longitudinally relative to the erected form of the carton.

Starting at the lefthand side of the blank ofPlG. l, a narrow glue tab is formed between the score line 11 and the edge extremity 21 of the blank. A series of transverse divider elements, to 'be described in more detail, are formed between the score lines 11, 12, and the divider elements, in the form shown, are horizontally disposed across the top of the carton body in the partially erected carton, as will be described. 7

A front wall 22 is formed between the score lines 12, 13, and a back wall 23 is formed between the score lines 17, 18 near the righthand end of the blank.

A of bottom wall panels 24, 25 are formed between the score lines 13, 14 and 16, 17, respectively, and a'pair of central partition panels 26, 27 are formed between the score lines 14, 15 and 15, 16, respectively, being joined along the score line 15. v i

A cover 28 is formed between the score lines 13, 19, and a cover locking flap 29 is formed between the score line 19 and the righthand edge extremity 30 of the blank Ltd. The cover flap 29, in accordance with known practice, is provided with a plurality of cover locking tabs 31 which, in the erected and closed carton, are engaged adjacent the front wall of the carton to lock the cover in its closed condition.

The area'of the blank forming the central partition panels 26, 27 is provided with a series of cut-outs, such as indicated at 32 to accommodate downward folding of divider elements in the erected carton. Certain of the cut-outs, at the ends of the carton and also in itscenter area, are shaped to provide hooklike projections 33 such that, when the carton is erected with the partition panels 26, 27 secured in back-to-back relation, the vertically oriented divider elements at the ends and at the center of the carton become lockingly engaged by the hooklike projections 33, all as described in more detail in the beforementioned Inman patents.

Also as described in the Inman patents, a plurality of generally U-shaped cuts 34 are provided in the bottom wall panels 24, 25, to form integral tablike elements 35 on the bottom edges of the partition panels 26, 27. The arrangement is such that, when the carton is erected, the tablike elements 35 project downward from the bottom edges of the partition panels to serve as legs or supports therefor. Advantageously, the supports 35 are provided adjacent each endvof the carton and also adjacent and on each side of its transverse center line.

Still referring to FIG. 1 of the'drawing, the area of the blank between the score lines 11, 12 is cut and scored to provide a plurality of divider elements. Specifically, in the illustrated carton, a first pair of corresponding divider elements 36 are provided at each end of the blank, and a second, pair ofcorresponding divider elements 37 are provided in the center area of the blank. Corresponding sets of narrow divider elements 38 are additionally provided between the end and center dividers 36, 37.

Each of the divider elements 36-38 is foldably hinged along a transverse score line 39, formed by a small gusset element 40, such that the divider elements may be folded from the plane of the blank into a plane at right angles thereto, or into vertical disposition in the erected carton.

in the erected carton, shown in end elevation in FIG. 3, the central partition panels 26, 27 are folded and secured in back-to-back relation, and the respective bottom wall panels 2%, 25 extend downward and outward therefrom to form a bottom structure of shallow, inverted V- shaped configuration, the depth of the V being determined by the height of the tablike supports 35 which project downward from the central partition panels. The front wall'22 extends upward from the outer edge of the bottom wall panel 24, and the panel from which the divider elements are cut extends horizontally across the top of the carton body, the glue strip 20 extending downward and being secured to the front surface of the back wall 23. The

upper margin of the back wall 23 extends upward to the top extremity of the partition formed by the panels 26, 27, and the cover 28 extends forward over the top of the carton. The cover flap 29 extends downward from the front edge of the cover,,and the cover locking tabs 31 are received between and interlocked with the various gusset elements 40 connecting the divider elements to the front wall 22.

Previous to erecting the carton, it is prepared in the form of a flattened tube by folding the blank along the score line 15 and adhesively or otherwise securing the partition panels 26, 27 in back-to-back relation. The

. blank is then folded about the score lines 14, 16, so that the bottom wall panels enfold the partition panels, and about a score line 41 which extends centrally through the various divider elements 36-38. The last-mentioned fold brings the glue strip 20 into face-to-face relation with the back wall 23, and the strip is adhesively or otherwise secured to the back wall to completethe flattened tube.

The carton is shipped in its flattened form and is erected by squaring the side walls, folding the divider elements into vertical orientation and folding over and closing the cover.

The carton as described thus far, is of known construction, following generally the principles of the beforementioned Inman patents. The specific improvements of the present invention, which are particularly applicable to the before-described carton construction but have wider application, are directed to the provision of a novel interlocking arrangement between selected ones of the divider elements and the bottom wall structure of the carton,

V the effect of which is to impart substantial additional strength to the bottom wall structure, enabling it to retain its desired and advantageous inverted V-shaped configuration, event though the panels 24, 25 forming the bottom wall become softened through the absorption of moisture or otherwise. Specifically, certain of the divider elements including at least the end dividers 36 are provided along their free edges with downwardly projecting locking tabs 42 of inverted T-shaped configuration, having enlarged head portions 43 and reduced stern portions 44. In the erected carton, the T-shaped locking tabs 43 project through the bottom wall of the carton, and the enlarged head portion 43 of the tabs engage and support the lower surface of the bottom wall panels, substantially as indicated in FIG. 3. Advantageously, the lower edge extremities 45 of the locking tabs 42 are arranged to lie in a base plane defined by the outer longitudinal edges 46, 47 of the bottom wall panels such that, when the erected carton is placed upon a supporting surface the lower edge extremities of the locking tabs 42 are engaged and supported directly by the surface.

Advantageously, the T-shaped locking elements 42 project through the bottom wall panels 24, 25 in the region of the openings left therein by the removal of the tablike supports or legs 35. Thus, thegenerally .U-shaped cutouts 34, when the partition panels 26, 27 are secured in back-to-back relation and the bottom wall panels 24, 25 are folded into the erected, V-shaped configuration, form openings 48 (FIG. 2 divided by the partition panels 26, 27, and the width of the stem 44 of the locking tab is related to the primary width of such openings in a man- I nor to be' received closely therein in the erected carton.

To permit the selected divider elements 36 to be folded into vertical disposition, when the carton is erected, accommodation must be made forthe enlarged head portion 43 of the T-shaped locking, element 42. In accordance with the invention, such accommodation is made by forming cut and stripped out openings 49 (FIG. 1) in the bottom wall panels 24, 25 immediately adjacent and connecting the U-shaped cuts 3 and offset somewhat in the blank from the folding axes of the divider elements 36. The arrangement is such that, in the erected carton, openings of keyhole configuration are provided adjacent the divider elements 36, with the keyhole shaped openings comprising reduced portions 48 and enlarged portions 50.

The reduced portions 48 of the keyhole shaped openings directly underliethe vertically oriented dividers 36, while the enlarged portions 50 of the openings are offset therefrom in the direction of the free end of the divider before folding. Thus, as the divider is folded from the plane of the blank into vertical orientation, the enlarged head portion 43 of the T-shaped locking element "is received in and passes through the enlarged portion 50 of the keyhole shaped opening. In the fully erected carton, the T-shaped locking element is received in the reduced portion 48 of the keyhole shaped opening, sothat the enlarged portion 43 of the locking element directly underlies portions of the bottom wall panels 24, 25 to provide the desired support therefor. To accommodate the presence of the central partition, the T-shaped locking'tabs42 are provided with a vertical slit 51 (FIG. 1) so that portions of the locking tab extend downward on each sideof the partition. (In a similar manner, the other divider elements of the carton are provided with vertical slits, not specifically identified, which accommodate the'presence of the central partition where required.) Advantageously, the locking tab is merely slit, rather than being provided with a cut-out slot of definite width, so that the two elements of the locking tab are spread apart as the divider element 36 is folded downward over the central; dividing partition. Thus, to accommodate proper separation of the two sections of the locking tab, and also' to provide for direct support between the dividers 36 and the central partition, each of the vertical slits 51 in .the dividers 36 is terminated by a cut 52 of inverted U-shaped form. The top portion of the inverted U-shaped cut 52 extends directly across the top of the vertical slit 51, and the downwardly extending leg portions of the cut 52 are directed toward but terminate short of the base of the stem of the T-shaped locking element 42. Thus, each section of the T-shaped locking element 42 is provided with a weakened axis or fold line lying essentially along an extension of the legs of the U-shaped cut 52.

As shown best in FIG. 2, when the divider elements 36 are folded downward into vertical disposition and the T-shaped locking tabs 42 are applied over the central partition, the separate elements of the locking tab tend to hinge slightly about the weakened axes extending from the U-shaped cuts 52. This causes the sections of the locking elements to lie at a slight angle to the central partition, so that the locking tabs frictionally grip the surfaces of the partition, effectively locking the dividers 36 in their erected vertical orientation.

The defined edge of the divider element 36, formed by the horizontal upper portion of the U-shaped cut 52, provides firm supporting engagement between the divider element and the central partition, imparting extra strength to the carton structure;

The improvement of the invention is specifically advantageous when employed in conjunction with the cartons of the design described and claimed in the beforementioned Inman patents. However, as will be understood, the principles of the invention are not necessarily limited to cartons of the specific construction described.

One of the particularly advantageous features of the invention resides in the utilization of a novel locking tab of inverted T-shaped configuration which is received through a central aperture in a V-shaped carton bottom to provide direct support to the lower surface of the bottom wall panels. Such support, being provided at the end extremities of the carton cells, does not significantly impair the cushioned support provided by the V-shaped bottom, but is highly effective in preventing undesirable sag of the carton bottom, due to softening of the paperboard material through moisture absorption or the like.

The specific form ofinterlocking bottom reinforcement provided by the present invention is especially advantageous in conjunction with the specific carton illustrated, since desirable and advantageous features of known carton constructions may be employed throughout other 6 areas of the carton, and little, if any, change is required in present carton erecting machinery to accommodate the improved carton structure.

It will be understood, of course, that the specific form of the invention herein illustrated and described is intended to be representative only, as certain changes may be made therein without departing from the clear teachings of the disclosure. For example and without implying any limitation, the T-shaped locking tabs 42 illustrated in conjunction with the end dividers 36 may, Where appropriate, be provided additionally in conjunction with the center dividers 37. Accordingly, reference should be made to the following appended claims in determining the full scope of the invention.

I claim:

1. An erectable egg carton or the like formed of sheet material and comprising, when in erected form,

(a) a central, vertical dividing partition formed of a pair of partition panels connected along upper edge portions and folded back to back,

(b) a bottom wall formed by a pair of bottom wall panels foldably connected along the bottom edges of the respective partition panels and extending outward and downward therefrom,

(c) a plurality of supporting legs integral with said partition panels and extending downward therefrom to a base plane defined by the outer longitudinal V edges of said bottom wall panels,

(d) said supporting legs comprising sections of sheet material cut from areas of said bottom wall panels such that, in the erected carton, said supporting legs project downward through cut-out openings formed by adjacent areas of opposed bottom wall panels,

( e) front and back walls formed by front and back wall panels foldably connected along the outer longitudinal edges of the bottom wall panels and extending upward therefrom,

(f) a cover structure foldably connected to the top longitudinal edge of the back wall, and

(g) a plurality of transverse divider elements formed by a cut and scored divider panel foldably connected along the top longitudinal edge of the front wall, extending across the top of the carton structure, and

7 having a margin secured to the back wall,

(It) said divider panel being cut and scored to form said plurality of dividers foldablyrconnected in the plane of the divider panel and extending downward toward the bottom wall and supportingly engaging said dividing partition,

(i) certain of said dividers having locking tabs of generally inverted T-shaped configuration extending below the bottom wall and lockingly engaging with the lower surfaces of said bottom wall panels over areas extending transversely outward from said partition.

2. The cart-on of claim 1, in which,

(a). said locking tabs extend downward substantially to said base plane to provide for the direct support of said certain dividers by a base surface.

3. The carton of claim 1, in which,

(a) said locking tabs, extend through certain of said cut-out openings formed in the bottom wall,

- (b) said certain cut-out openings being of keyhole configuration to accommodate the heads of the T- shaped locking tabs in enlarged areas of the openings and accommodating onlythe stems of the lock ing tabs in reduced areas of the openings.

4. The carton of claim 3, in which,

(a) the keyhole shaped openings are formed in part by cut-out material forming supporting legs.

5. The carton of claim 1, in which,

(a) said certain dividers are located at least at the respective longitudinal end extremities of said car-ton.

6. An erectable egg carton or the like formed of sheet material and comprising, when in erected form,

'7 (a) foldably connected central partition, bottom wall,

front wall, back wall and cover panels,

(b) the inner edges of said bottom wall panels being integral with and foldably connected to the bottom edges of said central partition panels; said central partition panels being foldably connected at their top edges along a predetermined score line; said bottom along said score line into a back-to-back relation ship,

(c) a plurality of dividers extending transversely across theopen carton cooperating with said partition to divide said carton into a plurality of cells, V

(at) said dividersbeing hingedly supported near their top edges by said front and back walls and extending downward toward said bottom wall, 7

(e) at least certain of said dividers having locking tabs of inverted T-shaped configuration straddling lower portions of the duplex partition and exerting a grip- (b) enlarged areas of said openings being more offset 7 from .said hinge axes than reduced areas of the openings,

(0) said enlarged areas being adapted to receive enlargedhead'portions of the T-shaped locking tabs when said certain dividers are folded into vertical disposition, and

(:1) said reduced areas closely receiving reduced stem portions of the T-shaped locking tabs when said certain dividers are vertically disposed. I

9. An erectable egg carton or the like formed of sheet material and comprising, when in erected form,

(a) a central, vertical dividing partition formed of a pair of partition panels connected along upper edge portions and folded back to back,

(b) a bottom wall formedby a pair of bottom wall panels 'foldably connected along the bottom edges of the respective partition panels and extending outward and downward therefrom,

(c) a plurality of supporting legs integral with said partition panels and extending downward therefrom to a base plane defined by the outer longitudinal edges of said bottom wall panels,

(d) said supporting legs comprising sections of sheet material cut from areas of said bottom wall panels such that, in the erected carton, said supporting legs project downward through cut-out openings formed by adjacent areas of opposed bottom wall panels,

(e) front and back walls formed by front and back wall panels foldably connected along the outer longitudinal edges of the bottom wall panels and extending upward therefrom,

(f) a cover structure foldably connected to the top longitudinal edge of the back wall, and

(g) a plurality of transverse divider elements formed by a cut and scored divider panel foldably connected along the top longitudinal edge of the front wall, extending across the top of the carton structure, and having a margin secured to the back wall,

8 (it) said div-iderpanel being cut and scored to form said plurality of dividers foldably connected in the plane of the divider panel and extending downward toward the bottom wall, (i) certain of said dividers having locking tabs of generally inverted T-shaped configuration extending below the bottom Wall and lockingly engaging with the lower surfaces of said bottom wall panels over areas extending transversely outward from said partition,

a (j) said locking tabs extending through certain of said cut-out openings formed in the bottom wall,

- (k) said certain cut-outopenings being of keyhole configuration to accommodate the heads of the T- shaped locking tabs in enlarged areas of the openings and accommodating only the stems of the locking tabs in reduced areas of the openings,

(1) said keyhole shaped openings being formed in part by cut-out material forming supporting legs,

(in) said cut-out material forming reduced area por- V tions of said keyhole shaped openings, and

(n) saidbottom wall panels having additional material cut outandstripped therefrom to form the enlarged area portions of said keyhole shaped openings.

10. An erectable egg carton or the like formed of sheet material and comprising, when in erected form,

(a) a central, vertical dividing partition formed of a pair of partition panels connected along upper edge portions and folded back to back,

(11) a bottom wall formed by a pair of bottom wall panels foldably connected along the bottom edges of the respective partition panels and extending outward and downward therefrom,

' (c) a plurality of supporting legs integral with said partition panels and extending downward therefrom to a base plane defined by the outer longitudinal edges of said bottom wall panels, t

(d) said supporting legs comprising sections of sheet material cut from areas of said bottom wall panels such that, in the erected carton, said supporting legs project downward through cut-out openings formed by adjacent areas of opposed bottom wall panels,

(e) front and back walls formed by front and back Wall panels foldably connected along the outer longitudinal edges of the bottom wall panels and extending upward therefrom,

(f) a cover structure foldably connected to the top longitudinal edge of the back wall, and

(g) a plurality of transverse divider elements formed by a cut and scored divider panel foldably connected along the top longitudinal edge of the front wall, extending across the top of the carton structure, and having a margin, secured to the back wall,

(/1) said divider panel being cut and scored to form said plurality of dividers foldably connected in the plane of the divider panel and extending downward toward the bottom wall, t

(i) certain of said dividers having. locking tabs of generally inverted T-shaped configuration extending below the bottom wall and lockingly engaging with the lower surfaces of said bottom wall panels over areas extending transversely outward from said a partition,

(j) said locking tabs being cut centrally and vertically upward from their lower edges .to receive portions of said partition, and

(k) said partition being notched downward from the top to receive unslotted portions of said locking tabs and said certain dividers from which they extend.

v9 1'5 nating above the principal lower edges of said cer- References Cited by the Examiner tain dividers and providing lines of low resistance to UNITED STATES PATENTS hinging movement of opposed sections of said locking tabs on opposite sides of the central vertical cuts therein, whereby said opposed sections swing sufficiently about said lines of low resistance to accom- 56 2 modate the presence of said central vertical cuts of 16179 1/ 2 Swanson 229*49 Said Partition GEORGE o. RALSTON, Primary Examiner.

2,106,613 1/38 Levkotf 22929 2,533,340 12/50 Allen. 

1. AN ERECTABLE EGG CARTON OR THE LIKE FORMED OF SHEET MATERIAL AND COMPRISING, WHEN IN ERECTED FORM, (A) A CENTRAL, VERTICAL DIVIDING PARTITION FORMED OF A PAIR OF PARTITION PANELS CONNECTED ALONG UPPER EDGE PORTIONS AND FOLDED BACK TO BACK, (B) A BOTTOM WALL FORMED BY A PAIR OF BOTTOM WALL PANELS FOLDABLY CONNECTED ALONG THE BOTTOM EDGES OF THE RESPECTIVE PARTITION PANELS AND EXTENDING OUTWARD AND DOWNWARD THEREFROM, (C) A PLURALITY FO SUPPORTING LEGS INTEGRAL WITH SAID PARTITION PANELS AND EXTENDING DOWNWARD THEREFROM TO A BASE PLANE DEFINED BY THE OUTER LONGITUDINAL EDGES OF SAID BOTTOM WALL PANELS, (D) SAID SUPPORTING LEGS COMPRISING SECTIONS OF SHEET MATERIAL CUT FROM AREAS OF SAID BOTTOM WALL PANELS SUCH THAT, IN THE ERECTED CARTON, SAID SUPPORTING LEGS PROJECT DOWNWARD THROUGH CUT-OUT OPENINGS FORMED BY ADJACENT AREAS OF OPPOSED BOTTOM WALL PANELS, (E) FRONT AND BACK WALLS FORMED BY FRONT AND BACK WALL PANELS FOLDABLY CONNECTED ALONG THE OUTER LONGITUDINAL EDGES OF THE BOTTOM WALL PANELS AND EXTENDING UPWARD THEREFROM, (F) A COVER STRUCTURE FOLDABLY CONNECTED TO THE TOP LONGITUDINAL EDGE OF THE BACK WALL, AND (G) A PLURALITY OF TRANSVERSE DIVIDER ELEMENTS FORMED BY A CUT AND SCORED DIVIDER PANEL FOLDABLY CONNECTED ALONG THE TOP LONGITUDINAL EDGE OF THE FRONT WALL, EXTENDING ACROSS THE TOP OF THE CARTON STRUCTURE, AND HAVING A MARGIN SECURED TO THE BACK WALL, (H) SAID DIVIDER PANEL BEING CUT AND SCORED TO FORM SAID PLURALITY OF DIVIDERS FOLDABLY CONNECTED IN THE PLANE OF THE DIVIDER PANEL AND EXTENDING DOWNWARD TOWARD THE BOTTOM WALL AND SUPPORTINGLY ENGAGING SAID DIVIDING PARTITION, (I) CERTAIN OF SAID DIVIDERS HAVING LOCKING TABS OF GENERALLY INVERTED T-SHAPED CONFIGURATION EXTENDING BELOW THE BOTTOM WALL AND LOCKINGLY ENGAGING WITH THE LOWER SURFACES OF SAID BOTTOM WALL PANELS OVER AREAS EXTENDING TRANSVERSELY OUTWARD FROM SAID PARTITION. 